Over-the-shoulder marching tubas typically have a cluster of tubing just to the left of the player's head which may impede the ability of the player to see to his/her left side. Consequently, drill writers for marching bands or drum corps typically accommodate for this impediment in the composition of field shows. In other words, the tuba player's maneuvers are limited to those requiring a clear view (guide) to the left. Other brass players (trumpet, horn, baritone, etc) generally do not suffer this limitation.